registry keys ???????

can anyone inform me about these i`ve just got a program that scans pc and you can delete invalid entries ? my question is all the entries it finds if i delete them will it harm my pc or make programs not work properly ??

it could depending on the complexity of the program.

best bet is to make sure that the program makes a full backup of the registry before making any changes to it.

you could search the net to find the location of your registry files to back them up manually on your operating system

I have used cc cleaner to do this and have found no problems what so ever with this software,but as nawabasif said it could be different for different programs